WASHINGTON -- Tests performed before the deadly blowout of
BP's oil well in the Gulf of Mexico should have raised doubts about
the cement used to seal the well, but the company and its cementing
contractor used it anyway, investigators with the president's oil
spill commission said Thursday.
It's the first finding from the commission looking into the
causes of the April 20 explosion that killed 11 workers and led to
the largest offshore oil spill in U.S. history. And it appears to
conflict with statements made by Halliburton Co., which has said
tests showed the cement mix was stable.
The cement mix's failure to prevent oil and gas from entering
the well has been identified by BP and others as one of the causes
of the accident.
BP and Halliburton decided to use a foam slurry created by
injecting nitrogen into cement to secure the bottom of the well, a
decision outside experts have criticized.
The panel says that of four tests conducted in February and
April by Halliburton, only one -- the last -- showed the mix would
hold. But the results of that single successful test were not
shared with BP, and may not have reached Halliburton, before the
cement was pumped, according to a letter sent to commissioners
Thursday by chief investigative counsel Fred Bartlit.
BP had in hand at the time of the blowout the results of only
one of the tests -- a February analysis sent to BP by Halliburton on
March 8 that indicated the cement could fail.
Halliburton (and perhaps BP) should have considered
redesigning the foam slurry before pumping it at the Macondo
well, Bartlit writes.
Independent tests conducted for the commission by Chevron on a
nearly identical mixture were also released Thursday. The results
conclude the cement mix was unstable, raising questions about the
validity of Halliburton's final test.
BP, as part of its internal investigation, also conducted tests
that showed the cement mix was flawed, but its analysis was
criticized by Halliburton, which said it was not the correct
formula. The company also said the testing Halliburton did on the
cement was incomplete.
By contrast, the commission obtained proprietary additives from
Halliburton as well as a recipe to recreate the slurry that was
used on the well.
A spokeswoman for Halliburton said the company was reviewing the
findings and would have a response later Thursday.
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Online:
Presidential Oil Spill Commission: www.oilspillcommission.gov
